Fan frame structure

ABSTRACT

A fan frame structure includes a frame having a bottom surface, a top surface and a flow passage. The flow passage is located between the bottom surface and the top surface, and the bottom surface and the top surface are provided with an outlet opening and an inlet opening, respectively, which are communicable with the flow passage. The outlet opening has an outlet edge, on and along which a plurality of notches communicable with the flow passage is cut. By providing the notches on the outlet edge, it is able to largely reduce the noise and the vibration produced when a fan operates.

FIELD OF THE INVENTION

The present invention relates to a fan frame structure, and more particularly, to a fan frame structure capable of largely reducing the noise produced during fan operation.

BACKGROUND OF THE INVENTION

Following the quick development of high performance, high frequency, high running speed and compact electronic products, the amount of heat produced by the electronic products is constantly increased, which tends to cause unstable operational state of the electronic products and thus affect the reliability and the service life thereof. Therefore, heat dissipation has become an important issue among the electronic products. To effectively dissipate the heat produced by the electronic products, a conventional way is forced heat dissipation by cooling airflows produced by a fan.

The principle of producing cooling airflows by fan is mostly related to the wing-shaped design of blades on a rotor of the fan. The rotor is driven by a motor and a circuit board to rotate at a nominal speed. When the wing-shaped blades are driven to rotate, work is done through the camber of the wing-shaped blades that produces a push force and accordingly, produces cooling airflows. Meanwhile, when the rotor rotates, the frame of the fan often produces undesired fundamental frequency vibration to cause additional noise. And, with the increasingly rigorous demands for heat dissipation by servers and other network communication equipment, the conventional fan with general rotational speed is no longer competent for use. Therefore, it is necessary to further enhance the fan rotational speed. In addition, the problem of high noise that comes from the entire fan and is caused by the turbulent airflows at the fan outlet also needs to be solved urgently.

According to the above description, the conventional fan has the disadvantages of (1) producing high noise when the fan operates at a high rotational speed; and (2) producing severe vibration when the fan operates.

SUMMARY OF THE INVENTION

A primary object of the present invention is to effectively solve the problems in the conventional fan by providing a fan frame structure that can largely reduce the noise produced when the fan operates.

Another object of the present invention is to provide a fan frame structure that can largely reduce the vibration produced when the fan operates.

To achieve the above and other objects, the fan frame structure according to the present invention includes a frame having a bottom surface, a top surface and a flow passage. The flow passage is located between the bottom surface and the top surface, and the bottom surface and the top surface are provided with an outlet opening and an inlet opening, respectively, which are communicable with the flow passage. The outlet opening has an outlet edge, on and along which a plurality of notches communicable with the flow passage is cut.

With the fan frame structure of the present invention, when airflows are discharged via the outlet opening to an environment outside the frame, the notches provided on the outlet edge allow the turbulent airflows at the outlet opening to contact with air outside the frame sooner. In this way, the noise produced when the fan operates can be reduced, and the vibration of the fan produced during its operation can also be largely reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein

FIG. 1 is a bottom perspective view of a fan frame structure according to a first embodiment of the present invention;

FIG. 2 is a top perspective view of the fan frame structure of FIG. 1;

FIG. 3 is a bottom perspective view of a fan frame structure according to a second embodiment of the present invention;

FIG. 4 is a bottom perspective view of a fan frame structure according to a third embodiment of the present invention;

FIG. 5 is a bottom perspective view of a fan frame structure according to a fourth embodiment of the present invention; and

FIG. 6 is a bottom perspective view of a fan frame structure according to a fifth embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described with some preferred embodiments thereof and by referring to the accompanying drawings. For the purpose of easy to understand, elements that are the same in the preferred embodiments are denoted by the same reference numerals.

Please refer to FIGS. 1 and 2, which are bottom and top perspective views, respectively, of a fan frame structure 2 according to a first embodiment of the present invention. As shown, the fan frame structure 2 in the first embodiment includes a frame 27 having a bottom surface 20, a top surface 21, a flow passage 22 and an inner sidewall surface 23. The flow passage 22 is located between the bottom surface 20 and the top surface 21, and faces toward the inner sidewall surface 23. The bottom surface 20 and the top surface 21 are provided with an outlet opening 24 and an inlet opening 25, respectively, and the inlet and the outlet opening 24, 25 are communicable with the flow passage 22.

In the flow passage 22 of the frame 27, a fan wheel 5 is correspondingly arranged. Since the fan wheel 5 has a structural configuration similar to that of conventional fan wheels, i.e. has a hub and a plurality of radially outward extended blades, it is not repeatedly described herein.

In addition, the fan frame structure 2 further includes a base 4, which is supported at the outlet opening 24 and connected to the frame 27 by a plurality of connecting members 40. In the first embodiment of the present invention, the connecting members 40 are illustrated as a plurality of ribs. However, it is understood the connecting members 40 are not necessarily limited to the form of ribs, but can be, for example, stationary blades or other equivalents.

The outlet opening 24 of the frame 27 has an outlet edge 240, which is a surface bent at an angle. In other words, the outlet edge 240 is a joint of the bottom surface 20 and the inner sidewall surface 23 of the frame 27. On and along the outlet edge 240, a plurality of notches 3 communicable with the flow passage 22 is cut. In the illustrated first embodiment, the notches are equally spaced along the outlet edge 240, i.e. the joint of the bottom surface 20 and the inner sidewall surface 23 of the frame 27. However, in other operable embodiments, for example the second embodiment of the present invention shown in FIG. 3, the notches 3 can be otherwise unequally spaced along the outlet edge 240. Further, in the illustrated first embodiment, each of the notches 3 are cut on the outlet edge 240 in a direction perpendicular to the outlet edge 240. That is, a junction of each notch 3 and the outlet edge 240 forms a right angle of 90°. However, in a third embodiment of the present invention as shown in FIG. 4, there are notches 3 cut on the outlet edge 240 in a direction not perpendicular to the outlet edge 240. That is, the junction of each notch 3 and the outlet edge 240 forms an included angle other than 90°. Moreover, the quantity and the size of the notches 3 are also adjustable according to the user's requirements.

Please refer to FIG. 5, which is a bottom perspective view of a fan frame structure according to a fourth embodiment of the present invention. In the fourth embodiment, the outlet edge 240 is a slant surface 26. That is, the slant surface 26 is formed at the joint of the inner sidewall surface 23 and the bottom surface 20 of the frame 27, and the notches 3 are cut on the slant surface 26. In the illustrated fourth embodiment, the notches 3 are long grooves in shape. In a fifth embodiment as shown in FIG. 6, the notches 3 can be isosceles triangles, equilateral triangles or isosceles trapezoids in shape. In other words, the notches 3 are changeable in shape according to the user's requirements to similarly achieve the effect of the present invention.

With the fan frame structure of the present invention, when airflows are discharged via the outlet opening 24 to an environment outside the frame 27, the notches 3 provided on the outlet edge 240 allow the turbulent airflows at the outlet opening 24 to contact with air outside the frame 27 sooner. In this way, the noise produced when the fan operates can be reduced, and the vibration of the fan produced during its operation can also be largely reduced.

Therefore, compared to the conventional fan frames, the fan frame structure of the present invention has the following advantages: (1) capable of largely reducing the noise produced when the fan operates at a high rotational speed; and (2) capable of largely reducing the vibration produced when the fan operates.

The present invention has been described with some preferred embodiments thereof and it is understood that many changes and modifications in the described embodiments can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims. 

1. A fan frame structure, comprising: a frame having a bottom surface, a top surface and a flow passage; the flow passage being located between the bottom surface and the top surface, and the bottom surface and the top surface being provided with an outlet opening and an inlet opening, respectively, which are communicable with the flow passage; and the outlet opening having an outlet edge, on and along which a plurality of notches communicable with the flow passage is cut.
 2. The fan frame structure as claimed in claim 1, wherein the notches are so cut on and along the outlet edge that they are either equally spaced, unequally spaced, or in a staggered arrangement.
 3. The fan frame structure as claimed in claim 1, wherein the outlet edge is selected from the group consisting of a surface bent at an angle and a slant surface.
 4. The fan frame structure as claimed in claim 1, wherein the notches have a shape selected from the group consisting of a groove, a triangle, a polygon, and an isosceles trapezoid.
 5. The fan frame structure as claimed in claim 1, wherein the notches can be cut on the outlet edge in a direction perpendicular to or not perpendicular to the outlet edge.
 6. The fan frame structure as claimed in claim 1, further comprising a base located in the flow passage; and the base being supported at the outlet opening and connected to the frame by a plurality of connecting members.
 7. The fan frame structure as claimed in claim 6, wherein the connecting members are selected from the group consisting of stationary blades and ribs.
 8. The fan frame structure as claimed in claim 1, wherein the flow passage has a fan wheel pivotally rotatably mounted therein.
 9. The fan frame structure as claimed in claim 1, wherein the frame has an inner sidewall surface facing toward the flow passage.
 10. The fan frame structure as claimed in claim 9, wherein the outlet edge is located between or at a joint of the inner sidewall surface and the bottom surface. 